.orange-buff animal canines chevrotain colored colorful colors coloured colourful colours deer delicate distinctive elongated-upper-jaw-canines even-toed-ungulate fur greater-Malay-chevrotain greater-mouse-deer herbivore herbivorous hooves large-eyed miniature mouse-deer napu nocturnal Singapore-zoo small solitary terrestrial territorial tiny tragulus-napu triangular-head trusting wet-swampy-habitat zoo